1. Field of the Invention
This invention relates generally to a vehicular windshield washer system in combination with a windshield wiper, and more particularly to improvements in the vehicular windshield washer system including two washer nozzles mounted on a wiper arm of the windshield wiper, arranged such that washer fluid ejection from the two washer nozzles is changed in accordance with swinging movement of the wiper arm.
2. Description of the Prior Art
A variety of vehicular windshield washer systems in combination with windshield wipers have been proposed and put into practical use in which two washer fluid nozzles are mounted on each wiper arm to alternately eject washer fluid onto a windshield on o the opposite sides of the wiper arm in accordance with the swinging movement of the Wiper arm. An example of such conventional vehicular windshield washer systems will be discussed with reference to FIGS. 23 and 24. In this windshield washer system, two washer nozzles 3, 4 are installed on a nozzle installation member 2 mounted on a wiper arm 1 to spray washer fluid from one of the washer nozzles 3, 4 onto a windshield 7' in response to the direction of rotational movement of the wiper arm during swinging operation of the wiper arm. Such a vehicle windshield washer system is disclosed, for example, in Japanese Utility Model Provisional Publication Nos. 48-62732 and 48-12727).
In such an arrangement, a change-over valve or the like for changing washer fluid supply is provided to accomplish ejection of washer fluid from one of the nozzles 3, 4 directed to the rotational or advancing direction of the wiper arm. A valve serving as such a change-over valve is disclosed, for example, in Japanese Utility Model Provisional Publication Nos. 62-32270, 62-24171, and 62-24172.
With such a change-over valve, changing washer fluid supply from one to the other nozzle is carried out at turning positions A, B at which the rotational movement direction of the wiper arm is changed over, and therefore washer fluid is continuously ejected in the rotational direction of the wiper arm until the wiper arm reaches the turning position A, B.
Such washer fluid ejection wastes washer fluid. Because wiping of the windshield 7' with washer fluid can be sufficiently accomplished even by supplying washer fluid to the nozzle until the wiper arm reaches a position slightly forward of the turning position A, B. Furthermore, according to the above conventional washer fluid ejection, when the wiper arm 1 rotationally moves towards the side of a front pillar 6 near a driver's seat, washer liquid is scattered sideward over the front pillar 6, thereby troubling pedestrains.